Mary I. Williams

Forest Restoration Paradigms

An estimated 2 billion ha of forests are degraded globally and global change suggests even greater need for forest restoration. Four forest restoration paradigms are identified and discussed: revegetation, ecological restoration, functional restoration, and forest landscape restoration. Restoration is examined in terms of a degraded starting point and an ending point of an idealized natural forest. Global change, climate variability, biotechnology, and synthetic biology pose significant challenges to current restoration paradigms, underscoring the importance of clearly defined goals focused on functional ecosystems. Public debate is needed on acceptable goals; one role for science is to inform and help frame the debate and describe feasibility and probable consequences.

Considerations for restoring temperate forests of tomorrow: Forest restoration, assisted migration, and bioengineering

Tomorrow’s forests face extreme pressures from contemporary climate change, invasive pests, and anthropogenic demands for other land uses. These pressures, collectively, demand land managers to reassess current and potential forest management practices. We discuss three considerations, functional restoration, assisted migration, and bioengineering, which are currently being debated in the literature and have the potential to be applied independently or concurrently across a variety of scales. The emphasis of functional restoration is to reestablish or maintain functions provided by the forest ecosystem, such as water quality, wildlife habitat, or carbon sequestration. Maintaining function may call upon actions such as assisted migration—moving tree populations within a species current range to aid adaptation to climate change or moving a species far outside its current range to avoid extinction—and we attempt to synthesize an array of assisted migration terminology. In addition, maintenance of species and the functions they provide may also require new technologies, such as genetic engineering, which, compared with traditional approaches to breeding for pest resistance, may be accomplished more rapidly to meet and overcome the challenges of invasive insect and disease pests. As managers develop holistic adaptive strategies to current and future anthropogenic stresses, functional restoration, assisted migration, and bioengineering, either separately or in combinations, deserve consideration, but must be addressed within the context of the restoration goal.